IPA: /ˌʌn.kəmˈbaɪnd/
KK: /ʌnˈkəmˌbaɪnd/
Not mixed or joined with anything else; existing separately.
The uncombined elements can be analyzed individually in the experiment.
Uncombined → It is formed from "un-" (meaning not) and "combined" (from Latin "combinare", meaning to join together). The word "uncombined" means not joined together or separate.
Think of 'not' ('un-') joined together ('combined') — that's why uncombined means something that is not joined.